The Biden administration proposed new regulations Thursday that if enacted would aggressively limit greenhouse gas emissions from power plants, the second-most harmful source of greenhouse gas emissions in the U.S. The move stands to force major changes in the energy sector and is likely to set up a legal battle with the energy industry.  

The Environmental Protection Agency said the new standards would enable the sector to avoid up to 617 million metric tons of carbon dioxide through 2042, which officials compared to taking roughly half the 300 million cars in the U.S. off the road. 

The EPA also estimates that the new rules would drastically improve air quality and public health, potentially avoiding more than 300,000 cases of asthma and 1,300 premature deaths every year by 2030. 

“The public health and environmental benefits of this proposed rule will be tremendous and we have more than enough reason to be optimistic about what’s possible for the future of our nation,” EPA Administrator Michael S. Regan said on a call Wednesday.

Power plants are a major source of greenhouse gas emissions in the U.S. Electricity production accounts for 25% of greenhouse gases, just behind the country’s leading source — the transportation industry. 

The majority of power plants in the U.S. are powered by fossil fuels. Last year, the burning of fossil fuels, such as coal and natural gas, generated about 60% of all electricity in the U.S., while approximately 22% came from renewable energy sources — wind, hydro and solar power — and 18% from nuclear energy.

President Joe Biden vowed early in his administration to decarbonize the power sector by 2035 and make the nation’s entire economy carbon neutral by 2050.

But these new standards would require power plants to fundamentally change operations either by installing carbon capture and storage technology, which takes carbon dioxide produced by the burning of fossil fuels out of the air and places it back into the earth, or by abandoning fossil fuels in favor of renewable energy sources. 

The EPA said that these proposed changes would result in “negligible” impacts to the price of electricity for consumers.

According to the International Energy Agency, there are currently 18 direct-air capture plants operating worldwide. Because the technology is so new, carbon capture is costly. In 2021, the first and only commercial power plant in the U.S. to utilize carbon capture technologies shut down outside of Houston after it was plagued by mechanical malfunctions and failed to meet its emissions targets. 

In its latest annual report, the U.N.’s Intergovernmental Panel on Climate Change conceded that while carbon capture is key to unlocking a green future, technological improvements need to be made to make the technology more cost effective and energy efficient.

Senior administration officials said on a call Tuesday that by their calculations, tax incentives provided by 2022’s Inflation Reduction Act should offset the cost of installing carbon capture and storage technologies. They also noted that the closed Texas plant which had been using carbon capture was reopening, in part thanks to those incentives. 

President Biden’s two predecessors both had power industry regulations struck down by the courts. 

Former President Donald Trump’s proposal to slightly cut plant emissions was overruled by a federal appellate court in 2021, and in 2016, the Supreme Court granted a stay on Barack Obama’s Clean Power Plan.

The new proposed rule is already facing some fierce opposition. West Virginia Democratic Senator Joe Manchin, in anticipation of Thursday’s announcement, railed against the Biden ad Wednesday that the Biden administration is “hellbent on doing everything in their power to regulate coal and gas-fueled power plants out of existence” and that he would not support any EPA congressional nominees until they “halt their government overreach.”

The EPA will take comments on these proposals from stakeholders for the next 60 days and hold a virtual public hearing before moving forward with potential legislation.